Abstract

The quest for understanding quantum matter that is either strongly interacting or out of equilibrium is at the forefront of modern physics. Since its inception, the field of ultracold atoms has provided an ideal setting for exploring quantum many-body phenomena, with key ingredients including the pristine control of atom-trapping geometries, the ability to coherently manipulate the atom’s internal states, the experimentally resolvable intrinsic timescales, and the unique ability to tune the interparticle interactions using Feshbach resonances. The advent of optical box traps offered pristine samples with homogeneous densities. This allowed more direct connections with many-body theories and qualitatively new measurements, and has revolutionized single-component quantum simulators for fundamental precision many-body physics. Transposing such box traps to both bosonic and fermionic spin mixtures recently has also hinted at their advantages in the vast realm of quantum mixtures.

In this talk, I will first showcase our work over the last decade using box-trapped single-component 39K Bose gases (featuring exquisite control over the interparticle interactions), with topics explored ranging from extreme wave phenomena to strongly correlated fluids. I will then detail our recent first experiments using homogeneous bosonic spin mixtures, where we studied the quantum dynamics of Bose polarons, which are paradigmatic quasiparticles that can form when impurities are immersed in a Bose–Einstein condensate. I will conclude with an outlook of my future research plans, where I envision a next-generation quantum simulator based on box-trapped quantum mixtures to investigate fundamental phenomena driven by quantum statistics, study far-from-equilibrium dynamics of open quantum systems, and explore the phase diagrams of exotic many-body systems with unconventional interactions.